Information processing apparatus displaying indices of video contents, information processing method and information processing program

ABSTRACT

In order to quicken switching of indices and reduce the time required for display after switching, a mobile phone includes a video content specifying portion to specify at least one video content, an index element generating portion to generate a thumbnail for a video content when accepting a generation instruction and to stop generation of the thumbnail when accepting a cancellation instruction, an index element generation requesting portion, in response to the event that a video content is specified by the video content specifying portion, to output a generation instruction including identification information identifying the specified video content to the index element generating portion, and a cancellation instructing portion to output a cancellation instruction to stop generation of the thumbnail for the already specified video content when a new video content is specified before completion of generation of the thumbnail for the already specified video content.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of application Ser. No. 11/865,992filed on Oct. 2, 2007, which claims priority to Japanese PatentApplication No. 2006-271184 filed with Japan Patent Office on Oct. 2,2006, the entire contents of these applications are hereby incorporatedby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an information processing apparatus, aninformation processing method, and an information processing program,and more particularly to an information processing apparatus thatdisplays indices of a plurality of video contents, an informationprocessing method, and an information processing program.

2. Description of the Prior Art

In recent years, reproduction apparatuses are in widespread use whichreproduce video contents recorded on recording media such assemiconductor memories and optical discs. When a plurality of videocontents are recorded on a recording medium, it is necessary to select adesired video content from among them, and generally a menu screen isdisplayed for use in such selection. When a menu screen includes, forone video content, character information such as a title of the videocontent as well as a thumbnail that is a reduced version of an image, itmay take time for the menu screen to be displayed. This is because theimage data included in the video content is encoded, and thus, a certainperiod of time is required to decode the coded image data in order togenerate the thumbnail. This problem occurs whether the image data is ofa stationary image or a moving image. Thus, there is known a techniquewhere, at the time of displaying a menu screen, an image such as anhourglass is displayed instead of a thumbnail before the thumbnail isgenerated, to inform the user that the thumbnail is being generated.Although a method of increasing the processing speed for the decodingprocessing may be conceivable, it would lead to an increased cost.

When the user performs another operation before the thumbnail isdisplayed on the menu screen, i.e., when the user performs an operationto scroll the menu screen for example, the reproduction apparatus wouldnot be able to accept the operation, or even if it could accept theoperation, it would not be able to execute the processing in accordancewith the operation, because of the heavy load of the decoding processingfor generating the thumbnail. This would require the user to wait untilthe menu screen is displayed, leading to degradation in responsivity ofthe reproduction apparatus.

BRIEF SUMMARY OF THE INVENTION

According to an aspect of the present invention, an informationprocessing apparatus includes: a video content specifying portion tospecify at least one of a plurality of video contents recorded on arecording medium; an index element generating portion, in response toacceptance of a generation instruction, to read a video contentidentified by identification information included in the generationinstruction from the recording medium and generate an index elementbased on the read video content, and, in response to acceptance of acancellation instruction, to stop generation of the index element basedon the video content identified by identification information includedin the cancellation instruction; a generation requesting portion, inresponse to the event that the video content is specified by the videocontent specifying portion, to output the generation instructionincluding the identification information identifying the specified videocontent to the index element generating portion; and a cancelingportion, when a new video content is specified by the video contentspecifying portion at a stage before the index element corresponding tothe video content already specified by the video content specifyingportion is generated by the index element generating portion, to outputthe cancellation instruction to stop generation of the index elementcorresponding to the already specified video content to the indexelement generating portion.

According to another aspect of the present invention, an informationprocessing method includes the steps of: specifying at least one of aplurality of video contents recorded on a recording medium; in responseto acceptance of a generation instruction, reading a video contentidentified by identification information included in the generationinstruction from the recording medium and generating an index elementbased on the read video content; in response to acceptance of acancellation instruction, stopping generation of the index element basedon the video content identified by identification information includedin the cancellation instruction; in response to the event that the videocontent is specified, outputting the generation instruction includingthe identification information identifying the specified video content;and when a new video content is specified at a stage before the indexelement corresponding to the already specified video content isgenerated, outputting the cancellation instruction to stop generation ofthe index element corresponding to the already specified video content.

According to a further aspect of the present invention, an informationprocessing program causes a computer to execute the steps of: specifyingat least one of a plurality of video contents recorded on a recordingmedium; in response to acceptance of a generation instruction, reading avideo content identified by identification information included in thegeneration instruction from the recording medium and generating an indexelement based on the read video content; in response to acceptance of acancellation instruction, stopping generation of the index element basedon the video content identified by identification information includedin the cancellation instruction; in response to the event that the videocontent is specified, outputting the generation instruction includingthe identification information identifying the specified video content;and when a new video content is specified at a stage before the indexelement corresponding to the already specified video content isgenerated, outputting the cancellation instruction to stop generation ofthe index element corresponding to the already specified video content.

The foregoing and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of a mobile phone according to anembodiment of the present invention.

FIG. 2 is a functional block diagram showing an example of the functionof the mobile phone.

FIG. 3 is a functional block diagram schematically showing the functionof a control portion.

FIG. 4 is a first diagram showing an example of an index table.

FIG. 5 is a first diagram showing an example of a menu screen.

FIG. 6 is a second diagram showing an example of the index table.

FIG. 7 is a second diagram showing an example of the menu screen.

FIG. 8 is a flowchart illustrating an example of the flow of menudisplay processing.

FIG. 9 is a flowchart illustrating an example of the flow of indexelement generation processing.

FIG. 10 is a flowchart illustrating an example of the flow of indexdisplay processing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An embodiment of the present invention will now be described withreference to the drawings. In the following description, like referencecharacters denote like parts, which have like names and functions, andtherefore, detailed description thereof will not be repeated.

FIG. 1 shows a mobile phone according to an embodiment of the presentinvention. Referring to FIG. 1, the mobile phone 1 includes anoperation-side portion 3 and a display-side portion 2. On an innersurface of operation-side portion 3, operation keys 14 including tenkeys, a call key and the like and a microphone 13 are arranged, and onan outer surface opposite to the inner surface, a camera 24, which willbe described later, is arranged. On an inner surface of display-sideportion 2, a liquid crystal display (LCD) 16 and a first speaker 11 arearranged. On a side surface of display-side portion 2, a second speaker12 is arranged. Although mobile phone 1 shown here is provided with LCD16, LCD 16 may be replaced by an organic EL (ElectroLuminescence)display.

Operation-side portion 3 and display-side portion 2 are rotatablyjointed to each other with a hinge mechanism, so that they can be openedand closed freely. The state of mobile phone 1 where mobile phone 1 isfolded and thus operation-side portion 3 and display-side portion 2 areclose to each other is called a closed style, while the state of mobilephone 1 where mobile phone 1 is opened and thus operation-side portion 3and display-side portion 2 are apart from each other is called an openstyle.

FIG. 2 shows an example of the function of the mobile phone. Referringto FIG. 2, mobile phone 1 includes: a control portion 21 for overallcontrol of mobile phone 1; a radio circuit 22 connected to an antenna22A; a codec portion 28 for processing audio data; microphone 13 andfirst speaker 11 respectively connected to codec portion 28; a tuner 23connected to antenna 22A; an AV decoder 29; a camera 24; an operationportion 25 to accept an input of an operation by a user; a displaycontrol portion 30 for controlling display on LCD 16; a RAM (RandomAccess Memory) 31 for use as a work area for control portion 21; a flashROM (Read Only Memory) 32 for storing, e.g., a program to be executed bycontrol portion 21; a vibration portion 26; a card interface (I/F) 27;and an external communication connection terminal 33 serving as a serialinterface.

Radio circuit 22 receives a radio signal that is received by antenna22A, and outputs an audio signal, obtained by demodulating the radiosignal, to codec portion 28. Further, radio circuit 22 receives an audiosignal from codec portion 28, and outputs a radio signal, obtained bymodulating the audio signal, to antenna 22A. Codec portion 28 decodes anaudio signal input from radio circuit 22, converts the decoded digitalaudio signal into an analog signal, and amplifies the same to be outputto first speaker 11. Further, codec portion 28 receives an analog audiosignal from microphone 13, converts the audio signal into a digitalsignal, and encodes the same and then outputs the coded audio signal toradio circuit 22.

Tuner 23 is connected to antenna 22A, and receives a broadcast signalthat is received by antenna 22A. The broadcast signal is ahigh-frequency digital modulated signal including video and audio data.Tuner 23 takes out a signal of a specific frequency from thehigh-frequency digital modulated signal input from antenna 22A. Further,tuner 23 is provided with a reverse interleave circuit and an errorcorrection circuit, and demodulates the obtained high-frequency digitalmodulated signal of the specific frequency and outputs the coded data toAV decoder 29. AV decoder 29 is provided with a video decoder and anaudio decoder, and decodes the coded data input from tuner 23 togenerate a video signal and an audio signal. It then subjects the videosignal to D/A (digital/analog) conversion to be output to displaycontrol portion 30, and also subjects the audio signal to D/A conversionto be provided to second speaker 12. While the case of receiving andreproducing the digital television broadcast waves is shown here by wayof example, the present invention is applicable to the case of receivingand reproducing analog television broadcast waves. Further, it may alsobe possible to receive and reproduce radio broadcast waves instead of,or in addition to, the television broadcast waves.

Display control portion 30, which is controlled by control portion 21,controls LCD 16 in accordance with an instruction input from controlportion 21 to cause it to display images. The images displayed on LCD 16include both moving and stationary images.

Camera 24 is provided with a lens and a photoelectric conversion elementsuch as a CMOS (Complementary Metal Oxide Semiconductor) sensor or thelike, where the lens collects light onto the CMOS sensor, and the CMOSsensor subjects the received light to photoelectric conversion andoutputs the obtained image data to control portion 21. Camera 24, underthe control of control portion 21, starts pickup of an image inaccordance with an instruction from control portion 21, and outputs theobtained stationary or moving image data to control portion 21. Camera24 is provided with an image processing circuit that carries out imageprocessing for improvement of the quality of the image of thephotoelectrically converted image data, and an A/D converter circuitthat converts the image data from analog data to digital data. Controlportion 21 outputs the stationary or moving image data output fromcamera 24 to display control portion 30 to be displayed on LCD 16, or,encodes the stationary or moving image data by compressive coding, andstores the same in flash ROM 32 or in a memory card 27A attached to cardI/F 27, so that the video content is recorded on memory card 27A.

Operation portion 25 includes operation keys 14 and a lamp 25A.Operation keys 14 accept an input of an operation by a user, and outputthe accepted operation to control portion 21. Lamp 25A emits light underthe control of control portion 21.

Removable memory card 27A is attached to card I/F 27. Memory card 27Amay be a CompactFlash, SmartMedia (registered trademarks), SD (SecureDigital) memory card, memory stick, MMC (MultiMedia Card), xD picturecard, or the like.

Control portion 21 can access memory card 27A via card I/F 27. When avideo content is recorded on memory card 27A, control portion 21 readsthe video content from memory card 27A and outputs the coded dataincluded in the video content to AV decoder 29. AV decoder 29 decodesthe coded data input from control portion 21 to generate video and audiosignals, and subjects the signals to D/A conversion. It then outputs theconverted video signal to display control portion 30 and outputs theconverted audio signal to second speaker 12, whereby the video contentis reproduced.

While the case of storing the program to be executed by control portion21 in flash ROM 32 is explained here by way of example, it may bepossible to store the program in memory card 27A and read the programfrom memory card 27A to be executed by control portion 21. The recordingmedium for storing the program is not restricted to memory card 27A. Itmay be a flexible disk, a cassette tape, an optical disc (CD-ROM(Compact Disc-ROM), MO (Magnetic Optical Disc), MD (Mini Disc), DVD(Digital Versatile Disc)), an optical card, or a semiconductor memorysuch as a masked ROM, an EPROM (Erasable Programmable ROM), or the like.Alternatively, mobile phone 1 may be connected to the Internet via radiocircuit 22 and download the program from a computer connected to theInternet to be executed by control portion 21. As used herein, the“program” includes, not only the program directly executable by controlportion 21, but also a source program, a compressed program, anencrypted program, and others.

FIG. 3 schematically shows the function of the control portion.Referring to FIG. 3, control portion 21 includes: a display instructionaccepting portion 51 to accept an instruction to display a menu screen;a scroll instruction accepting portion 53 to accept an instruction toscroll the displayed menu screen; a video content specifying portion 61to specify at least one of a plurality of video contents recorded onmemory card 27A; an index element generation requesting portion 63 torequest generation of an index element of the specified video content;an index element generating portion 70 to generate an index element; amenu display control portion 67 to display an index corresponding to thevideo content specified by video content specifying portion 61; and acancellation instructing portion 65 to instruct stoppage of generationof the index element.

When the user depresses a pre-assigned key in operation keys 14 toinstruct display of a menu screen, display instruction accepting portion51 accepts a display instruction from operation portion 25. The menuscreen includes an index for a video content stored in memory card 27A.Display instruction accepting portion 51 outputs the accepted displayinstruction to video content specifying portion 61.

When the display instruction is input, video content specifying portion61 specifies at least one of a plurality of video contents recorded onmemory card 27A to display an index thereof on the menu screen. Here, itis assumed that the menu screen includes at most three indices. Thus,when the display instruction is input, video content specifying portion61 specifies three video contents from among the video contents storedin memory card 27A, and outputs identification information foridentification of the specified three video contents to both indexelement generation requesting portion 63 and menu display controlportion 67. Here, it is configured to assign serial numbers to theplurality of video contents stored in memory card 27A and use the serialnumbers as the identification information of the video contents. Theserial numbers may be determined in accordance with the feature valuesof the video contents, such as file names, dates of storage, or dataamounts of the respective video contents. Alternatively, the user maydesignate the feature values of the video contents for use indetermination of the serial numbers.

While the case of using the serial numbers assigned to the videocontents as the identification information is explained here, theidentification information may be unique information provided to thevideo contents, which may be file names thereof. In such a case, it isunnecessary to assign the serial numbers to the video contents.Furthermore, it may also be configured such that video contentspecifying portion 61 arbitrarily specifies any three video contents.

When the identification information of a video content is input fromvideo content specifying portion 61, index element generation requestingportion 63 outputs, to index element generating portion 70, aninstruction (generation instruction) including the relevantidentification information to generate an index element. When a displayinstruction is input to video content specifying portion 61, videocontent specifying portion 61 outputs identification information ofthree video contents to index element generation requesting portion 63,and correspondingly, index element generation requesting portion 63outputs three generation instructions, including the input threeidentification information items respectively, to index elementgenerating portion 70.

Index element generating portion 70 generates an index element based onthe video content. Here, the index element includes a thumbnail andcharacter information for the video content. Index element generatingportion 70 includes: a video content reading portion 71 to read a videocontent from memory card 27A; a decoding portion 73 to decode coded dataincluded in the video content to output an image; a reducing portion 75to reduce the image output from decoding portion 73 in size to generatea thumbnail; and a character information extracting portion 77 toextract character information included in the video content.

Video content reading portion 71 receives a generation instruction fromindex element generation requesting portion 63. When a generationinstruction is input, video content reading portion 71 reads the videocontent specified by the identification information included in thegeneration instruction from memory card 27A, and outputs the read videocontent to both decoding portion 73 and character information extractingportion 77.

Decoding portion 73 decodes coded data included in the video content.The coded data corresponds to the data obtained by encoding moving orstationary image data. Decoding portion 73 decodes the coded data andoutputs an image to reducing portion 75. In the case where the codeddata is one obtained by encoding moving image data, decoding portion 73selects one frame of the moving image, and outputs an image of theselected frame to reducing portion 75. Here, it may be configured toselect a first one of a plurality of frames of the moving image, or maybe configured to select a predetermined frame or an arbitrary frame.

Reducing portion 75 reduces the size of the input image to generate athumbnail. It then outputs the generated thumbnail to menu displaycontrol portion 67 together with the identification information of thevideo content. The thumbnail image has a predetermined resolution.

Character information extracting portion 77 extracts characterinformation included in the video content, and outputs the extractedcharacter information to menu display control portion 67 together withthe identification information of the video content. The video contentincludes character information in a predetermined portion thereof, whichinformation is extracted by character information extracting portion 77.

While index element generating portion 70 can output the characterinformation immediately after input of a generation instruction, itcannot output the thumbnail immediately, because a certain period oftime is required for decoding the coded data for generation of thethumbnail. Thus, index element generating portion 70 generates a processof implementing the functions of video content reading portion 71,decoding portion 73, reducing portion 75, and character informationextracting portion 77. More specifically, index element generatingportion 70 generates an independent process every time a generationinstruction is input. The process executes processing independent ofanother process. When index element generation requesting portion 63outputs a plurality of generation instructions, index element generatingportion 70 generates processes of the same number as that of thegeneration instructions input from index element generation requestingportion 63. The processes correspond to the identification informationitems included in the respective generation instructions, and arespecified by the identification information items.

The process generated by index element generating portion 70 ceases toexist when character information extracting portion 77 outputs thecharacter information and reducing portion 75 outputs the thumbnail. Itis also nullified when a cancellation instruction is input, which willbe described later. When a display instruction is input to video contentspecifying portion 61, video content specifying portion 61 outputs theidentification information items of three video contents to indexelement generation requesting portion 63, and in turn, index elementgeneration requesting portion 63 outputs three generation instructionscorresponding respectively to the input three identification informationitems to index element generating portion 70. In this case, indexelement generating portion 70 generates three processes correspondingrespectively to the three identification information items included inthe input three generation instructions.

It is noted that index element generating portion 70 may have a circuitconfiguration. Specifically, since the menu screen includes at mostthree indices, index element generating portion 70 may have threecircuits each including video content reading portion 71, decodingportion 73, reducing portion 75, and character information extractingportion 77. In this case, index element generation requesting portion 63is configured to output three generation instructions to the threecircuits, respectively.

When the identification information of a video content is input fromvideo content specifying portion 61, menu display control portion 67generates a menu screen including the index of the video contentspecified by the identification information, and outputs the same todisplay control portion 30. Accordingly, the menu screen generated bymenu display control portion 67 is displayed on LCD 16.

Menu display control portion 67 receives, from index element generatingportion 70, the character information and the thumbnail together withthe identification information at different timings. Thus, menu displaycontrol portion 67 generates a menu screen in which an indexcorresponding to the identification information input from video contentspecifying portion 61 is associated with the character information inputtogether with the identification information identical to the relevantidentification information. Further, at the stage where the thumbnailthat is to be input together with the identification informationidentical to the identification information input from video contentspecifying portion 61 has not been input yet, menu display controlportion 67 generates a menu screen in which a mark indicating that thethumbnail is being generated is assigned to the index corresponding tothe relevant identification information. Here, an image representing anhourglass is used as the mark indicating that the thumbnail is beinggenerated, although not restricted thereto, the mark may be anyinformation that can explicitly inform the user that the thumbnail isbeing generated, like a character string “GENERATING”. When a thumbnailis input from index element generating portion 70, menu display controlportion 67 generates a menu screen having the thumbnail associated withthe index corresponding to the identification information that is inputtogether with the thumbnail.

More specifically, menu display control portion 67 generates an indextable in flash ROM 32. FIG. 4 shows an example of the index table.Referring to FIG. 4, the index table includes a record in whichidentification information of the video content, a first index elementand a second index element are associated with each other. The firstindex element corresponds to a thumbnail for the video contentidentified by the identification information, or a mark indicating thatthe thumbnail is being generated. The second index element correspondsto character information extracted from the video content identified bythe identification information.

Returning to FIG. 3, when the identification information of a videocontent is input from video content specifying portion 61, menu displaycontrol portion 67 generates a record including the identificationinformation in the index table. At this stage, the mark indicating thatthe thumbnail is being generated, which is a file name of the imagerepresenting an hourglass in this example, is stored in the field of thefirst index element in the generated record, and a blank is set for thefield of the second index element. When character information is inputfrom index element generating portion 70, menu display control portion67 stores the character information in flash ROM 32, while applying afile name thereto, and also stores the file name of the characterinformation in the field of the second index element in the record onthe index table that includes the same identification information as theone input together with the relevant character information. Further,when a thumbnail is input from index element generating portion 70, menudisplay control portion 67 stores the thumbnail in flash ROM 32, whileapplying a file name thereto, and also stores the file name of thethumbnail in the field of the first index element in the record on theindex table that includes the same identification information as the oneinput together with the relevant thumbnail.

Every time the index table is updated, menu display control portion 67selects three records from among the records included in the updatedindex table, and generates a menu screen based on the selected threerecords, which is output to display control portion 30.

The index table shown in FIG. 4 includes: a record having identificationinformation “1” of the first video content, a file name “aaa.gif” of thethumbnail, and a file name “aaa.txt” of the character informationassociated with each other; a record having identification information“2” of the second video content, a file name “bbb.gif” of the thumbnail,and a file name “bbb.txt” of the character information associated witheach other; and a record having identification information “3” of thethird video content, a file name “clock.gif” of the hourglass image, anda file name “ccc.txt” of the character information associated with eachother. Shown in FIG. 4 is the index table at the stage where, after adisplay instruction is accepted by display instruction accepting portion51, the thumbnails for the first and second video contents have beengenerated in index element generating portion 70, whereas the thumbnailfor the third video content has not been generated yet.

FIG. 5 shows an example of the menu screen. The menu screen shown inFIG. 5 is one generated by menu display control portion 67 based on theindex table shown in FIG. 4. While a rectangular area provided with thecharacters “THUMBNAIL” and its file name is shown in the figure, animage (thumbnail) having that file name is displayed in effect. Further,while a rectangular area provided with the characters “CHARACTERINFORMATION” and its file name is shown in the figure, the characterinformation having that file name is actually displayed. For the indexof the video data having the identification information “3”, the imageof the hourglass and the character information of the file name“ccc.txt” are displayed.

Returning to FIG. 3, when the user depresses a scroll key assigned inadvance in operation keys 14 to change the index to be displayed on themenu screen, scroll instruction accepting portion 53 accepts a scrollinstruction from operation portion 25. Scroll instruction acceptingportion 53 outputs the accepted scroll instruction to video contentspecifying portion 61.

When the scroll instruction is input, video content specifying portion61 specifies a next one of the plurality of video contents recorded onmemory card 27A, and outputs the identification information foridentification of the specified video content to both index elementgeneration requesting portion 63 and menu display control portion 67.Here, since the serial numbers are assigned to the video contents storedin memory card 27A, the video content having the number following thenumber of the last video content specified theretofore is specified.

Every time the scroll instruction is input, video content specifyingportion 61 specifies a video content. Thus, the identificationinformation items of the same number as that of the input scrollinstructions are output. As such, when the user inputs scrollinstructions successively, generation instructions of the numbercorresponding to the number of the input scroll instructions are inputfrom index element generation requesting portion 63 to index elementgenerating portion 70.

Meanwhile, when a scroll instruction is accepted at scroll instructionaccepting portion 53, menu display control portion 67 receives theidentification information from video content specifying portion 61.Menu display control portion 67 deletes the first index on the menuscreen, and generates a menu screen including the index of the videocontent specified by the newly input identification information as thelast index, and outputs the same to display control portion 30. Morespecifically, when the identification information of a new video contentis input from video content specifying portion 61, menu display controlportion 67 generates and adds a record including the relevantidentification information to the index table. It then selects the lastthree records on the index table, and generates a menu screen based onthe selected three records, which is output to display control portion30. Further, menu display control portion 67 outputs, to cancellationinstructing portion 65, the identification information of the videocontent the index of which is no longer necessary to be displayed on themenu screen.

There may be a case where the index deleted from the menu screen doesnot include a thumbnail, depending on the input number of times ofscroll instructions. This corresponds to the case, for example, whenthree scroll instructions are input successively at the stage where themenu screen shown in FIG. 5 is displayed. An example of the index tablecorresponding to this case is shown in FIG. 6, where three records arenewly added compared to the index table shown in FIG. 4. FIG. 7 showsanother example of the menu screen, which is generated by menu displaycontrol portion 67 based on the index table shown in FIG. 6. While thethumbnail for the video content having the identification information“3” is not displayed on the menu screen shown in FIG. 5, the menu screenshown in FIG. 7 displayed after successive input of three scrollinstructions does not include the index for the video content having theidentification information “3”.

Meanwhile, since the generation instruction including the identificationinformation “3” is already input to index element generating portion 70,index element generating portion 70 continues to generate the thumbnailfor the video content having the identification information “3”. Thus,cancellation instructing portion 65 outputs a cancellation instructionto cause index element generating portion 70 to stop generation of thethumbnail for the video content having the identification information“3”. That is, at the stage before the thumbnail for the video contentidentified by “3” is generated by index element generating portion 70,if the identification information “3” of the video content for which itis no longer necessary to display the index on the menu screen is inputfrom menu display control portion 67, cancellation instructing portion65 outputs the cancellation instruction to stop generation of thethumbnail, including the relevant identification information “3”, toindex element generating portion 70. More specifically, cancellationinstructing portion 65 reads the record including the identificationinformation “3” input from menu display control portion 67 out of theindex table stored in flash ROM 32, and refers to the first indexelement in the record to determine whether the file name stored in thefield of the first index element corresponds to the file name of thethumbnail. If the file name stored in the field of the first indexelement is not the file name of the thumbnail but that of the hourglassimage, cancellation instructing portion 65 outputs the cancellationinstruction including the identification information “3” to indexelement generating portion 70.

When a cancellation instruction is input, index element generatingportion 70 causes decoding portion 73 to stop decoding of the videocontent identified by the identification information included in thecancellation instruction, whereby the process generated for eachidentification information is nullified.

As such, in the case where a certain index is no longer necessary to bedisplayed on the menu screen, index element generating portion 70 stopsgeneration of the index element included in the index, and thus, it ispossible to reduce the load on control portion 21. Correspondingly, menudisplay control portion 67 can change the index displayed on the menuscreen more speedily. Furthermore, index element generating portion 70can generate a next thumbnail earlier in time.

While control portion 21 includes index element generating portion 70 inthe present embodiment, index element generating portion 70 may beconfigured independently of control portion 21.

FIG. 8 is a flowchart illustrating an example of the flow of menudisplay processing. The menu display processing is carried out bycontrol portion 21 as it executes an index display program. Referring toFIG. 8, control portion 21 determines whether a display instruction of amenu screen has been accepted (step S01). When the user depresses apre-assigned key in operation keys 14 to instruct display of a menuscreen, a display instruction is accepted from operation portion 25.Control portion 21 is in the standby mode until the display instructionis accepted, and once the display instruction is accepted, the processproceeds to step S02. That is, the menu display processing is carriedout on the condition that a display instruction is accepted.

In step S02, a variable N is set as 1. Variable N, representing theserial number assigned to each of a plurality of video contents storedin memory card 27A, corresponds to the identification information foridentification of the video content. In the following step S03, thevalue of variable N is set to a variable I. Variable I corresponds tothe identification information of the video content corresponding to theindex to be displayed initially, or in the first place, on the menuscreen. Since it is configured such that indices for three videocontents are to be displayed on a menu screen, the indices of the videocontents having the identification information of variables I, I+1 andI+2, respectively, are displayed on the menu screen.

In step S04, the I-th video content is set as a processing target. It isthen determined whether generation of an index element for the I-thvideo content has already been requested (step S05). If the generationof the index element has not yet been requested, the process proceeds tostep S06; whereas if it has already been requested, the process proceedsto step S08. In step S06, a generation instruction to instructgeneration of an index element is output. The generation instructionincludes identification information “I” of the I-th video content thathas been set as the processing target. In the following step S07, a newrecord is added to the index table in flash ROM 32. The new recordincludes the identification information “I” of the I-th video content.

In the following step S08, variable I is incremented, and the processproceeds to step S09. In step S09, it is determined whether variable Iis greater than a value (N+T 1). The constant T represents the number ofindices that can be displayed on a menu screen, which is “3” in thisexample. If variable I is greater than the value (N+T 1), the processproceeds to step S10; otherwise, the process returns to step S04. Whenthe process proceeds to step S10, generation instructions to generateindex elements for the N-th through (N+T 1)-th video contents,respectively, are output.

Hereinafter, index element generation processing will be described. FIG.9 is a flowchart illustrating an example of the flow of the indexelement generation processing, which is carried out by control portion21 as it executes the index display program. The index elementgeneration processing is carried out as one process generated by controlportion 21, which process is independent of the process of executing themenu display processing described above. Therefore, one or moreprocesses to carry out the index element generation processing may begenerated.

Referring to FIG. 9, control portion 21 determines whether a generationinstruction has been accepted (step S31). The generation instruction isinput from the process of carrying out the menu display processing.Control portion 21 is in the standby mode until a generation instructionis accepted (NO in step S31), and once the generation instruction isaccepted, the process proceeds to step S32. That is, the process ofcarrying out the index element generation processing is carried out onthe condition that the generation instruction is accepted from theprocess of carrying out the menu display processing. Thus, the processof carrying out the index element generation processing is identified bythe identification information included in the generation instruction bythe process of carrying out the menu display processing. It is notedthat control portion 21 may generate the process of carrying out theindex element generation processing at the time point when the processof carrying out the menu display processing outputs a generationinstruction.

In step S32, the identification information of the video contentincluded in the generation instruction is acquired. The video contentidentified by the identification information is read out of the videocontents stored in flash ROM 32 (step S33), and character information isextracted from the read video content (step S34). Then, the extractedcharacter information is output together with the identificationinformation acquired in step S32 (step S35). The destination of thecharacter information is the process of carrying out the menu displayprocessing that had output the generation instruction.

In the following step S36, decoding of the coded data included in thevideo content read in step S33 is started. Then, in step S37, it isdetermined whether a cancellation instruction has been accepted. Thecancellation instruction, which will be described later, is output bythe process of carrying out the menu display processing, and includesthe identification information of the video content. If the cancellationinstruction is accepted, the process proceeds to step S38; otherwise,the process proceeds to step S40. In step S38, the identificationinformation included in the cancellation instruction accepted in stepS37 is acquired.

Then, in the following step S39, it is determined whether theidentification information included in the cancellation instruction isidentical to the identification information included in the generationinstruction accepted in step S31. If so, the process is terminated;otherwise, the process proceeds to step S40. In step S40, it isdetermined whether decoding of the coded data started in step S36 iscompleted. If so, the process proceeds to step S41; otherwise, theprocess returns to step S37. That is, the process is terminated in thecase where the decoding of the coded data has been started in step S36and the cancellation instruction is accepted before completion of thedecoding. In contrast, if the decoding is completed before acceptance ofthe cancellation instruction, the process proceeds to step S41.

In step S41, it is determined whether the image obtained as a result ofdecoding is a moving image. If so, the process proceeds to step S42;otherwise, the process proceeds to step S43, skipping the step S42. Instep S42, one frame is extracted from the moving image. The first frameof the moving image may be extracted, or alternatively, a predeterminedframe or an arbitrary frame may be extracted.

In step S43, the image is reduced in size to generate a thumbnail, and,in step S44, the generated thumbnail is output together with theidentification information acquired in step S32. The destination of thethumbnail is the process of carrying out the menu display processingthat had output the generation instruction.

Returning to FIG. 8, in step S10, the index display processing iscarried out. FIG. 10 is a flowchart illustrating an example of the flowof the index display processing. Referring to FIG. 10, control portion21 determines whether character information has been accepted (stepS21). The character information is output from the process of carryingout the index element generation processing described above. If thecharacter information is accepted, the process proceeds to step S22;otherwise, the process proceeds to step S24.

In step S22, the identification information output together with thecharacter information by the process of carrying out the index elementgeneration processing is accepted. It is noted that the identificationinformation may be acquired by identifying the process that outputs thecharacter information. In such a case, the process of carrying out theindex element generation processing outputs only the characterinformation; it does not need to output the identification information.In the following step S23, the character information is stored in theindex table stored in flash ROM 32, and the process proceeds to stepS24. More specifically, the character information accepted in step S21is applied with a file name, and is stored in flash ROM 32, and the filename of the character information is stored in the field of the secondindex element of the record that includes the identification informationaccepted in step S22.

In the following step S24, it is determined whether a thumbnail has beenaccepted. The thumbnail is output from the process of carrying out theindex element generation processing described above. If the thumbnail isaccepted, the process proceeds to step S25; otherwise, the processproceeds to step S27.

In step S25, the identification information output together with thethumbnail by the process of carrying out the index element generationprocessing is accepted (step S25). It is noted that the identificationinformation may be acquired by identifying the process that outputs thethumbnail. In such a case, the process of carrying out the index elementgeneration processing only needs to output the thumbnail, which does notneed to output the identification information. In the following stepS26, the thumbnail is stored in the index table stored in flash ROM 32,and the process proceeds to step S28. More specifically, the thumbnailaccepted in step S24 is applied with a file name and stored in flash ROM32, and the file name of the thumbnail is stored in the field of thefirst index element of the record that includes the identificationinformation accepted in step S25.

Meanwhile, in step S27, a mark indicating that the thumbnail is beinggenerated is stored in the index table stored in flash ROM 32, and theprocess proceeds to step S28. More specifically, the file name of thehourglass image stored in advance in flash ROM 32 is stored in the fieldof the first index element of the record that includes theidentification information accepted in step S25.

In step S28, the N-th through (N+T 1)-th indices are displayed. Sinceconstant T is “3” in this example, the indices are specificallydisplayed as follows. The record including the identificationinformation “N” is read from flash ROM 32 and an index including theimage having the file name corresponding to the first index element andthe character information having the file name corresponding to thesecond index element of the read record is displayed as a first index indisplay order; the record including the identification information “N+1”is read from flash ROM 32 and an index including the image having thefile name corresponding to the first index element and the characterinformation having the file name corresponding to the second indexelement of the read record is displayed as a second index in displayorder; and the record including the identification information “N+2” isread from flash ROM 32 and an index including the image having the filename corresponding to the first index element and the characterinformation having the file name corresponding to the second indexelement of the read record is displayed as a third index in displayorder. As such, a menu screen including the three indices is displayed.In the case where a display instruction is accepted, the menu screenincludes: the index of the first video content as the first index indisplay order, the index of the second video content as the second indexin display order, and the index of the third video content as the thirdindex in display order.

Returning to FIG. 8, in step S11, it is determined whether a scrollinstruction has been accepted. When the user depresses a scroll keyassigned in advance in operation keys 14 to change the index on the menuscreen, a scroll instruction is accepted from operation portion 25. Ifthe scroll instruction is accepted, the process proceeds to step S12;otherwise, the process proceeds to step S15. In step S12, it isdetermined whether the thumbnail for the N-th video content has beenacquired. If so, the process proceeds to step S14; otherwise, theprocess proceeds to step S13. The thumbnail for the N-th video contentis the one that is no longer necessary to be displayed after acceptanceof the scroll instruction. Control portion 21 reads the record includingthe identification information “N” from the index table stored in flashROM 32, and determines whether the file name of the image of thethumbnail is stored in the field of the first index element. If the filename of the thumbnail image is stored, it is determined that thethumbnail for the N-th video content has been acquired. If the file nameof the thumbnail image is not stored, it is determined that thethumbnail for the N-th video content has not been acquired yet.

That the thumbnail for the N-th video content has not been acquiredmeans that the thumbnail is being generated in the process of carryingout the index element generation processing. Thus, in step S13, acancellation instruction to stop generation of the thumbnail is output.The cancellation instruction includes the identification information“N”. Among the plurality of processes of carrying out the index elementgeneration processing, the process that accepted the generationinstruction including the identification information “N” accepts thecancellation instruction and stops the processing. This can reduce theload on control portion 21. In the case where the process of carryingout the menu display processing can identify the plurality of processesof carrying out the index element generation processing, thecancellation instruction may be output to the process specified by theidentification information “N”. In such a case, the generationinstruction does not need to include the identification information.

In step S14, variable N is incremented, and the process proceeds to stepS15. In step S15, it is determined whether a termination instruction hasbeen accepted. When the user depresses a pre-assigned key in operationkeys 14 to instruct termination of display of the menu screen, atermination instruction is accepted from operation portion 25. If thetermination instruction is accepted, the process is terminated;otherwise, the process returns to step S03.

In the case where step S10 is executed after the scroll instruction isaccepted in step S11, variable N before acceptance of the scrollinstruction is incremented by “1” after the scroll instruction isaccepted. Thus, after the scroll instruction is accepted, the firstindex that was displayed on the menu screen before acceptance of thescroll instruction (i.e., the index of the N-th video content that wasdisplayed as the first index in display order) is not displayed, andinstead thereof, a new index is displayed on the menu screen as thethird index in display order.

As described above, according to mobile phone 1 of the presentembodiment, when a scroll instruction is input at the stage where thethumbnail for a video content is not yet displayed on the menu screen,generation of the thumbnail for the video content that is no longernecessary to be displayed on the menu screen is stopped, which reducesthe load on control portion 21. This increases the speed of change ofthe index displayed on the menu screen. In other words, it is possibleto quicken switching of the indices being displayed. Further, sinceindex element generating portion 70 can generate the next thumbnailearlier in time, the response time until the menu screen is displayedafter input of the scroll instruction can be reduced. In other words, itis possible to reduce the time required to display the index afterswitching the indices being displayed.

While mobile phone 1 has been described as an example of the informationprocessing apparatus in the above embodiment, the information processingapparatus may be a reproduction apparatus such as a disk reproductionapparatus or the like, as long as it displays indices for a plurality ofvideo contents stored in a recording medium. Further, not limited to theinformation processing apparatus, the present invention may of course beunderstood as an information processing method or an informationprocessing program for carrying out the processing illustrated in FIGS.8-10.

Although the present invention has been described and illustrated indetail, it is clearly understood that the same is by way of illustrationand example only and is not to be taken by way of limitation, the spiritand scope of the present invention being limited only by the terms ofthe appended claims.

The invention claimed is:
 1. An information processing apparatuscomprising: a storing portion to store video data; a generating portionto read said video data from said storing portion, and to generate afirst thumbnail corresponding to a first image of the video data bydecoding the video data to form the first image and reducing the firstimage to form the first thumbnail; and a display portion to display saidfirst thumbnail, wherein said generating portion, in response to anacceptance of a scroll instruction, generates a second thumbnail to benext displayed by said display portion by decoding the video data toform a second image and reducing the second image to form the secondthumbnail, wherein if the scroll instruction is received prior tocompletion of generation of the first thumbnail, generation of the firstthumbnail is cancelled and generation of the second thumbnail iscommenced.
 2. The information processing apparatus according to claim 1,wherein: the display portion displays a third image while the generatingthe first or second thumbnail.
 3. The information processing apparatusaccording to claim 2, wherein: the third image includes an hourglassimage.
 4. An information processing method executed by an informationprocessing apparatus which comprises a storing portion to store videodata, said information processing method comprising the steps of:reading said video data from said storing portion; generating a firstthumbnail corresponding to a first image of said video data by decodingthe video data to form the first image and reducing the first image toform the first thumbnail; displaying said first thumbnail; and inresponse to an acceptance of a scroll instruction, generating a secondthumbnail to be next displayed in said displaying step by decoding thevideo data to form a second image and reducing the second image to formthe second thumbnail, wherein if the scroll instruction is receivedprior to completion of generation of the first thumbnail, generation ofthe first thumbnail is cancelled and generation of the second thumbnailis commenced.
 5. A non-transitory computer-readable recording mediumencoded with an information processing program executed in a computercontrolling an information processing apparatus which comprises astoring portion to store video data, said information processing programcausing said computer to execute the steps of: reading said video datafrom said storing portion; generating a first thumbnail corresponding toa first image of said video data; displaying said first thumbnail; andin response to an acceptance of a scroll instruction, generating asecond thumbnail to be next displayed in said displaying step bydecoding the video data to form a second image and reducing the secondimage to form the second thumbnail, wherein if the scroll instruction isreceived prior to completion of generation of the first thumbnail,generation of the first thumbnail is cancelled and generation of thesecond thumbnail is commenced.